Total Deposition (TDep) Science Committee
Agricultural Stakeholder Workgroup Webinar Series Presents:
Atmospheric Nitrogen Deposition: Sources, Impacts, and Management
Recorded on November 20, 2024
Agenda
Presentation:
Atmospheric Reduced Nitrogen: Sources, Transformations, Effects, and Management
Charles T. Driscoll – University Professor of Environmental Systems and
Distinguished Professor
Syracuse University – Department of Civil and Environmental Engineering
Syracuse, NY
Summary: Human activities have increased atmospheric emissions and deposition of oxidized and reduced forms of nitrogen, but emission control programs have largely focused on oxidized nitrogen. Emissions of reduced nitrogen largely originate from livestock waste and fertilizer application, with contributions from transportation sources in urban areas and biomass burning. Observations suggest a discrepancy between trends in emissions and deposition of reduced nitrogen in the U.S., likely due to an underestimate in emissions. In the atmosphere, ammonia reacts with oxides of sulfur and nitrogen to form fine particulate matter that impairs health and visibility and affects climate forcings. Recent reductions in emissions of sulfur and nitrogen oxides have limited partitioning with ammonia, decreasing long-range transport. Satellite remote sensing has potential for monitoring atmospheric concentrations and emissions of ammonia, but there remains a need to maintain and strengthen ground-based measurements and continue development of chemical transport models. Elevated nitrogen deposition has decreased plant and soil microbial biodiversity and altered the biogeochemical function of terrestrial, freshwater, and coastal ecosystems. Decreases in deposition of reduced nitrogen could alleviate exceedances of critical loads for terrestrial and freshwater indicators in many U.S. areas.
Additional Information:
Atmospheric Reduced Nitrogen: Sources, Transformations, Effects, and Management
https://doi.org/10.1080/10962247.2024.2342765
Previous Webinar Recordings:
David Gay – Brief Overview of the Livestock and Poultry Environmental Learning Community (LPELC) Webinar “Role of Agriculture in Atmospheric Nitrogen Deposition: Sources, Impacts, and Management
Robert Sabo – Cleaner Air, Cleaner Water? Impacts of Atmospheric Nitrogen Deposition on Water Resources in the United States
Questions?
For further information contact Ian Rumsey at rumsey.ian@epa.gov